The purpose of this work is primarily twofold. First, to maintain a colony of inbred Buffalo strain rats in which we have successfully induced adenocarcinoma following the administration of 1-2, dimethylhydrazine subcutaneously and subsequently have established two transplantable tumor lines. One, an adenocarcinoma has been serially passed to the 21st generation. The other, a singet ring cell adenocarcinoma, has been successfully passed to the 18th generation. Both tumor lines are similar to human colon tumor counterparts, in morphological structure and biologic behavior - they metastasize readily and are lethal. Secondly, we are extending studies in biologic behavior - to their effects in female animals. In addition, we are assessing tumor growth and spread and the effect of tumor ablation at specific times during progressive stages of tumor growth.